Independent of the actual index profile of a single-cladded dispersion-shifted single-mode fiber, it is shown that the loss components given in the headline at the zero dispersion wavelength λ0accurately can be obtained by simple expressions that only depend on the Laplace spot size value at λ0. Withlambda_{0} = 1.55 mum, these relations are used to estim...
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New and existing one-sided rearrangeable switching networks are described, which minimize the number of optical switches required to interconnectNoptical terminals. Technical problems are identified. The potential size of one-sided rearrangeable networks, employing single-mode optical fiber, and the corresponding performance requirements of optical switches, are established.
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SM and GI fibers have been prepared by the low-pressure PCVD process using fluorine as the main dopant and small amounts of GeO2as codopant. Compared to pure fluorine doping, these fibers showed markedly improved optical properties. High N.A. (delta approx 2percent) GI fibers with Rayleigh scattering losses as low as 1.0 dB μm4/ km as well as "deeply depressed...
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Temperature sensor of the integrated optic structure was constructed using a Michelson interferometer configuration with an asymmetricXjunction and a grooved reflector on a LiNbO3substrate. With this structure, larger difference in the optical paths lengths for two beams is provided to realize higher sensitivity. Also a humidity sensor of the optical guided-wave structure is ...
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The1.2/1.3 mum band single-mode fiber WDM was developed with various factors such as characteristics, stability, and cost of the device in practical use taken into consideration. It uses ball-lens collimators in the optical coupling system. Utilizing its coupling characteristics could realize a low-loss high-stability WDM. An insertion loss variation is less than 0.25 dB throughout the ...
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Tunable laser action has been obtained in Nd3+- and Er3+-doped single-mode fiber lasers. In the case of the Nd3+-doped fiber, an extensive tuning range of 80 nm has been achieved. Tunable CW lasing also has been observed for the first time in an Er3+-doped fiber laser, which has an overall tuning range of 25 nm in the region oflambda = 1.54 /mu View full abstract»

For economic reasons, the drawing rate of optical fibers should be as high as possible. However, a high drawing rate introduces problems with respect to on-line coating of the fiber such as insufficient cooling down of the fiber before coating and application of an absolutely bubble-free concentric coating layer. A cooling device and a force-feed coating applicator are described that enable proper...
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The separation between lead and transducer losses in an intensity-modulated fiber sensor is solved by placing the transducer within a radio-frequency fiber Fabry-Perot filter performing a passive amplitude-phase conversion on the signal delivered by an amplitude-modulated source. An application is demonstrated in the case of a proximity sensor.
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An experimental high-speed optical time-division switching system has been realized. The system is able to exchange digitally encoded color video signals at 256-Mbit/s highway speed. Bistable laser diodes and directional coupler switch matrices are adopted as optical memories and optical read/write gates, respectively, in an optical time switch. The bistable laser diode operates as an optical flip...
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The first monolithic high-speech light source, consisting of an InGaAsP/InP DFB laser, metal-insulator-semiconductor field-effect transistors, and a monitoring photodiode, has been fabricated. Small-signal modulation bandwidth up to 4 GHz was successfully achieved. The device design, fabrication procedures, and operating characteristics for the integrated light source are described.
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Self-amplitude modulation due to group velocity dispersion (chromatic dispersion of an optical fiber) in phase-shift keying (PSK) coherent optical transmission systems is presented. It may place a serious limitation on performance of such systems by limiting the maximum transmission distance attainable at a given bit rate. The maximum transmission distance for any prescribed degree of self-amplitu...
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Most of interferometric temperature optical fiber sensors (O.F.S.) have a narrow dynamic range. In this paper we present both polarimetric and interferometric temperature O.F.S.. It is a single arm two-waves interferometer using Fresnel reflections at the end faces of the fiber. A controlled birefringence is induced in this fiber by tension coiling around a thermally expandable cylinder. We presen...
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This paper reports on the first experimental study in the large-signal domain on the relation between the linewidth enhancement factor α and the frequency chirp of picosecond pulses from diode lasers. The time-bandwidth product is found to be constant over a wide range of operating conditions, in good agreement with theory. Different laser structures in the same material (GaAs) are shown to h...
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A two-dimensional optooptical addressing system for fiber-array interconnections is described. The optical beam is deflected by a dynamic holographic grating. The characteristics of this grating are automatically adapted in a passive way to assure maximum efficiency during commutation process.
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The lower bound in loss for fusion splices is ∼ 0.01 dB due principally to lateral offset of the cores and alteration of the index profile. This paper investigates the effects on loss of viscous flow and diffusion of the glass constituents during fusion, defining their time-temperature dependencies, and changes in index profile.
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Low-loss fibers containing rare-earths have been produced with high absorption levels in the visible and near infrared regions. Although containing relatively large quantities of rare-earth impurity dopants, the fibers possess low-loss windows where the attenuation is similar to that observed in undoped fibers. This attribute makes the fibers attractive for use in long distributed sensors, as well...
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Phased-locked arrays of buried-ridge InP/InGaAsP diode lasers, emitting at 1.3 μm, were investigated both theoretically and experimentally. These arrays consist of index-guided buried-ridge lasers which are coupled via their evanescent optical fields. The field patterns and the modal gains of the array supermodes were calculated by using a simple waveguide model. The theoretical results show ...
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Statistics of partition noise, including covariances between modes, have been measured for gain-guided lasers at 850 nm. The results are discussed in the light of theories of partition noise and their implications for practical systems are explained.
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Aims & Scope

The Journal of Lightwave Technology is comprised of original contributions, both regular papers and letters, covering work in all aspects of optical guided-wave science, technology, and engineering. Manuscripts are solicited which report original theoretical and/or experimental results which advance the technological base of guided-wave technology. Tutorial and review papers are by invitation only. Topics of interest include the following: fiber and cable technologies, active and passive guided-wave componentry (light sources, detectors, repeaters, switches, fiber sensors, etc.); integrated optics and optoelectronics; and systems, subsystems, new applications and unique field trials. System oriented manuscripts should be concerned with systems which perform a function not previously available, out-perform previously established systems, or represent enhancements in the state of the art in general.